[1] Nagoya Univ, Biosci Ctr, Nagoya, Aichi 4648601, Japan
[2] Univ Calif San Diego, Dept Biol, La Jolla, CA 92093 USA
[3] Univ Calif San Diego, Ctr Genet Mol, La Jolla, CA 92093 USA
[4] Nagoya Univ, Grad Sch Bioagr Sci, Nagoya, Aichi 4648601, Japan
[5] Univ Tokyo, Grad Sch Sci, Dept Biophys & Biochem, Bunkyo Ku, Tokyo 113, Japan
[6] Univ Osnabruck, Abt Mikrobiol, D-49076 Osnabruck, Germany
[7] Chiba Univ, Fac Pharmaceut Sci, Chiba 2638522, Japan